The present invention relates to a foreign material interference detection apparatus for opening/closing members, and more particularly, to a foreign material interference detection apparatus for opening/closing members, such as a sliding roof, a power window, and a sliding door.
In the prior art, an automobile sunroof apparatus having a foreign material interference prevention apparatus, similar to that of a power window, has been proposed to detect foreign material interference when a sliding glass roof is being completely closed, to stop immediately the closing action, and move the glass in the opposite, or opening direction.
Generally, the rotating cycle (rotating speed) of a sliding motor for sliding the sliding glass roof is detected, and when the rotating cycle becomes long (when the rotating speed decreases gradually), foreign material interference is detected.
However, when completely closing the sliding glass roof while driving along a rough road, the vibrations applied to the automobile fluctuate the load applied to the sliding motor, which changes the rotating cycle (rotating speed) of the motor. The change in the rotating cycle (rotating speed) results in erroneous detection of foreign material interference.
Accordingly, a method using a digital filter, such as an FIR filter or an IIR filter, has been proposed to eliminate load fluctuations caused by external disturbances, such as vibrations. However, the load applied to the CPU with respect to the computations, such as sum/product calculations, is high. Thus, a CPU having higher speed is necessary. This increases the cost of the foreign material interference prevention apparatus. Further, load fluctuations caused by vibrations cannot be completely eliminated by the digital filter.
It is a first object of the present invention to provide a foreign material interference prevention apparatus that reduces the computation load for determining external disturbance.
It is a second object of the present invention to provide a foreign material interference prevention apparatus that accurately determines foreign material interference by completely eliminating load fluctuations, such as vibrations, while reducing the computation load for detecting interference.
A first aspect according to the present invention provides a foreign material interference detection apparatus for an opening/closing member. A drive source opens and closes the opening/closing member. A speed detection means detects the opening and closing speed of the opening/closing member and generates a detection signal. A data row dividing processing means obtains the opening and closing speed of the opening/closing member from the detection signal and divides the data into a plurality of groups. A speed fluctuation calculation means calculates fluctuations in the opening and closing speed based on the data of each of the divided groups. An external disturbance determination means compares the calculation result of the speed fluctuation calculation means and a predetermined value to determine an external disturbance. An interference determination means determines whether or not foreign material is interfering with the opening/closing member based on the calculation result of the speed fluctuation calculation means and the determination result of the external disturbance determination means.
A second aspect of the present invention provides a foreign material interference detection apparatus for an opening/closing member. A drive motor opens and closes an opening/closing member. A speed detecting means detects a rotating speed of the drive motor and generates a detection signal. A rotating cycle calculation processing means calculates a rotating cycle as load determination rotating cycles using the detection signal from the speed detecting means. A calculation processing means determines whether the rotating speed is fluctuating due to a load the same as that produced by foreign material interference based on the fluctuated value of the load determination rotating cycles obtained by the rotating cycle calculation processing means and counts the consecutive number of times in which the rotating speed is determined to have fluctuated by a load that is the same as that produced by foreign material interference. An interference determination processing means determines that there is foreign material interference if the calculation processing means determines that the applied load is the same as that produced when foreign material is interfering with the opening/closing member and the determination is made consecutively for a predetermined number of times.